The utility of organofluorine compounds as surface-active agents (i.e., surfactants) and surface-treating agents is due in large part to the extremely low free-surface energy of a C6–C12 fluorocarbon group, according to H. C. Fielding, “Organofluorine Compounds and Their Applications,” R. E. Banks, Ed., Society of Chemical Industry at p. 214 (1979). Generally, the organofluorine substances described above are those which have carbon-bonded fluorine in the form of a monovalent fluoroaliphatic radical such as a perfluoroalkyl group, typically —CnF2n+1, where n is at least 3, the terminal part of which group is trifluoromethyl, —CF3.
U.S. Pat. No. 5,453,540 (Dams et al.) describes fluorochemical compositions for the treatment of textiles comprising: (i) a fluorochemical oligomeric portion comprising an aliphatic backbone with a plurality of fluoroaliphatic groups attached thereto, each fluoroaliphatic group having a fully fluorinated terminal group and each independently linked to a carbon atom of the aliphatic backbone through an organic linking group;(ii) an organic moiety (which can be functional or non-functional, and which is different from the fluorochemical oligomeric portion); (iii) a non-polymeric isocyanate-derived linking group which links the fluorochemical oligomeric portion to the organic moiety; and (iv) a group bonded thereto, which can impart soft hand, stain release, water repellency, or a durable property when the compound is applied to a fibrous substrate.
Despite the various publications there continues to be a need for further fluorochemical compositions for the treatment of fibrous substrates to impart desired properties thereto such as water repellency, water-proofness, oil repellency and stain resistance. Yet further, although fluorochemical compositions have been employed for this purpose, the compositions have provided little or no antisoiling properties without degradation of the repellency properties. Thus it is desirable to provide a composition that can provide both durable repellency and antisoiling properties to fibrous substrates. It is further desired that such fluorochemical compositions be readily produced in a cost effective way, have sufficient storage stability and are efficient even if applied in low quantities to the substrate.